Revert "Disable LLVM's MergeFunctions again"
Revert "Disable LLVM's MergeFunctions again"

Renable the merge function pass. More bugs in LLVM's MergeFunction pass were
fixed.

This reverts commit r29248.

rdar://20920907

Swift SVN r29409

uasys/swift,xwu/swift,JGiola/swift,arvedviehweger/swift,IngmarStein/swift,zisko/swift,sschiau/swift,roambotics/swift,xwu/swift,frootloops/swift,jopamer/swift,johnno1962d/swift,swiftix/swift.old,zisko/swift,slavapestov/swift,jmgc/swift,zisko/swift,kusl/swift,felix91gr/swift,rudkx/swift,MukeshKumarS/Swift,OscarSwanros/swift,dduan/swift,brentdax/swift,Jnosh/swift,KrishMunot/swift,benlangmuir/swift,nathawes/swift,JGiola/swift,mightydeveloper/swift,MukeshKumarS/Swift,gregomni/swift,devincoughlin/swift,zisko/swift,brentdax/swift,natecook1000/swift,jopamer/swift,mightydeveloper/swift,dreamsxin/swift,adrfer/swift,glessard/swift,practicalswift/swift,ahoppen/swift,austinzheng/swift,swiftix/swift,SwiftAndroid/swift,jopamer/swift,parkera/swift,arvedviehweger/swift,johnno1962d/swift,khizkhiz/swift,manavgabhawala/swift,tardieu/swift,kusl/swift,johnno1962d/swift,allevato/swift,rudkx/swift,ben-ng/swift,djwbrown/swift,JaSpa/swift,deyton/swift,xedin/swift,cbrentharris/swift,return/swift,djwbrown/swift,KrishMunot/swift,uasys/swift,cbrentharris/swift,brentdax/swift,harlanhaskins/swift,kentya6/swift,Jnosh/swift,calebd/swift,airspeedswift/swift,tkremenek/swift,shajrawi/swift,cbrentharris/swift,frootloops/swift,gribozavr/swift,calebd/swift,glessard/swift,codestergit/swift,Ivacker/swift,kperryua/swift,arvedviehweger/swift,devincoughlin/swift,JaSpa/swift,tinysun212/swift-windows,KrishMunot/swift,apple/swift,SwiftAndroid/swift,stephentyrone/swift,xedin/swift,airspeedswift/swift,stephentyrone/swift,gottesmm/swift,danielmartin/swift,emilstahl/swift,ahoppen/swift,kusl/swift,allevato/swift,CodaFi/swift,atrick/swift,brentdax/swift,rudkx/swift,gribozavr/swift,hughbe/swift,jtbandes/swift,emilstahl/swift,stephentyrone/swift,sdulal/swift,JaSpa/swift,russbishop/swift,austinzheng/swift,apple/swift,karwa/swift,KrishMunot/swift,parkera/swift,JGiola/swift,devincoughlin/swift,Jnosh/swift,MukeshKumarS/Swift,ben-ng/swift,tardieu/swift,djwbrown/swift,kusl/swift,sdulal/swift,gribozavr/swift,aschwaighofer/swift,adrfer/swift,calebd/swift,kperryua/swift,kentya6/swift,felix91gr/swift,gmilos/swift,SwiftAndroid/swift,austinzheng/swift,zisko/swift,uasys/swift,JaSpa/swift,mightydeveloper/swift,milseman/swift,sdulal/swift,nathawes/swift,therealbnut/swift,tardieu/swift,OscarSwanros/swift,lorentey/swift,milseman/swift,aschwaighofer/swift,return/swift,Jnosh/swift,modocache/swift,tjw/swift,modocache/swift,kentya6/swift,slavapestov/swift,shajrawi/swift,OscarSwanros/swift,rudkx/swift,IngmarStein/swift,hughbe/swift,sschiau/swift,natecook1000/swift,kusl/swift,JaSpa/swift,MukeshKumarS/Swift,IngmarStein/swift,slavapestov/swift,slavapestov/swift,manavgabhawala/swift,Ivacker/swift,felix91gr/swift,mightydeveloper/swift,austinzheng/swift,adrfer/swift,Jnosh/swift,djwbrown/swift,amraboelela/swift,kstaring/swift,sschiau/swift,kusl/swift,calebd/swift,JGiola/swift,practicalswift/swift,Jnosh/swift,nathawes/swift,arvedviehweger/swift,ben-ng/swift,uasys/swift,amraboelela/swift,shajrawi/swift,karwa/swift,jmgc/swift,glessard/swift,karwa/swift,shajrawi/swift,therealbnut/swift,IngmarStein/swift,roambotics/swift,KrishMunot/swift,kperryua/swift,djwbrown/swift,hooman/swift,jtbandes/swift,xedin/swift,xwu/swift,shahmishal/swift,emilstahl/swift,KrishMunot/swift,tkremenek/swift,aschwaighofer/swift,apple/swift,johnno1962d/swift,gottesmm/swift,swiftix/swift.old,amraboelela/swift,LeoShimonaka/swift,benlangmuir/swift,kentya6/swift,gribozavr/swift,airspeedswift/swift,kentya6/swift,hooman/swift,gribozavr/swift,russbishop/swift,shahmishal/swift,KrishMunot/swift,CodaFi/swift,IngmarStein/swift,devincoughlin/swift,shajrawi/swift,therealbnut/swift,LeoShimonaka/swift,jmgc/swift,sschiau/swift,jckarter/swift,slavapestov/swift,amraboelela/swift,xwu/swift,karwa/swift,bitjammer/swift,huonw/swift,tkremenek/swift,natecook1000/swift,Ivacker/swift,deyton/swift,austinzheng/swift,khizkhiz/swift,airspeedswift/swift,hooman/swift,allevato/swift,jtbandes/swift,airspeedswift/swift,swiftix/swift,sschiau/swift,ahoppen/swift,emilstahl/swift,LeoShimonaka/swift,jckarter/swift,alblue/swift,swiftix/swift,frootloops/swift,shahmishal/swift,allevato/swift,sdulal/swift,xwu/swift,danielmartin/swift,jtbandes/swift,parkera/swift,devincoughlin/swift,modocache/swift,adrfer/swift,khizkhiz/swift,gregomni/swift,gregomni/swift,roambotics/swift,hooman/swift,practicalswift/swift,codestergit/swift,lorentey/swift,parkera/swift,ken0nek/swift,adrfer/swift,codestergit/swift,russbishop/swift,frootloops/swift,sschiau/swift,jmgc/swift,swiftix/swift,shahmishal/swift,amraboelela/swift,harlanhaskins/swift,dreamsxin/swift,benlangmuir/swift,jckarter/swift,milseman/swift,huonw/swift,huonw/swift,ahoppen/swift,alblue/swift,kperryua/swift,zisko/swift,calebd/swift,manavgabhawala/swift,felix91gr/swift,johnno1962d/swift,modocache/swift,danielmartin/swift,huonw/swift,ken0nek/swift,ahoppen/swift,SwiftAndroid/swift,shahmishal/swift,lorentey/swift,devincoughlin/swift,JGiola/swift,kentya6/swift,hooman/swift,austinzheng/swift,nathawes/swift,glessard/swift,kentya6/swift,nathawes/swift,LeoShimonaka/swift,therealbnut/swift,manavgabhawala/swift,huonw/swift,LeoShimonaka/swift,khizkhiz/swift,deyton/swift,hooman/swift,tkremenek/swift,swiftix/swift.old,tjw/swift,tinysun212/swift-windows,russbishop/swift,atrick/swift,swiftix/swift,MukeshKumarS/Swift,swiftix/swift.old,harlanhaskins/swift,gottesmm/swift,bitjammer/swift,danielmartin/swift,kusl/swift,devincoughlin/swift,felix91gr/swift,kstaring/swift,roambotics/swift,harlanhaskins/swift,alblue/swift,swiftix/swift.old,swiftix/swift.old,lorentey/swift,LeoShimonaka/swift,jopamer/swift,felix91gr/swift,shajrawi/swift,bitjammer/swift,jckarter/swift,amraboelela/swift,cbrentharris/swift,aschwaighofer/swift,return/swift,khizkhiz/swift,benlangmuir/swift,bitjammer/swift,stephentyrone/swift,ben-ng/swift,shahmishal/swift,LeoShimonaka/swift,karwa/swift,cbrentharris/swift,khizkhiz/swift,danielmartin/swift,emilstahl/swift,cbrentharris/swift,ahoppen/swift,shajrawi/swift,tkremenek/swift,calebd/swift,tardieu/swift,lorentey/swift,gregomni/swift,gregomni/swift,xedin/swift,tkremenek/swift,kstaring/swift,hughbe/swift,modocache/swift,tjw/swift,milseman/swift,parkera/swift,johnno1962d/swift,huonw/swift,return/swift,cbrentharris/swift,karwa/swift,CodaFi/swift,practicalswift/swift,mightydeveloper/swift,jtbandes/swift,gottesmm/swift,kperryua/swift,harlanhaskins/swift,dduan/swift,roambotics/swift,alblue/swift,hughbe/swift,zisko/swift,return/swift,gmilos/swift,glessard/swift,Ivacker/swift,swiftix/swift.old,swiftix/swift.old,slavapestov/swift,stephentyrone/swift,huonw/swift,allevato/swift,uasys/swift,Jnosh/swift,atrick/swift,bitjammer/swift,stephentyrone/swift,frootloops/swift,slavapestov/swift,nathawes/swift,parkera/swift,OscarSwanros/swift,harlanhaskins/swift,atrick/swift,parkera/swift,practicalswift/swift,stephentyrone/swift,swiftix/swift,ken0nek/swift,brentdax/swift,jopamer/swift,danielmartin/swift,SwiftAndroid/swift,jckarter/swift,benlangmuir/swift,IngmarStein/swift,gmilos/swift,sdulal/swift,mightydeveloper/swift,jtbandes/swift,karwa/swift,JaSpa/swift,amraboelela/swift,LeoShimonaka/swift,frootloops/swift,emilstahl/swift,MukeshKumarS/Swift,lorentey/swift,alblue/swift,return/swift,lorentey/swift,bitjammer/swift,mightydeveloper/swift,gribozavr/swift,brentdax/swift,tinysun212/swift-windows,Ivacker/swift,uasys/swift,Ivacker/swift,jckarter/swift,natecook1000/swift,khizkhiz/swift,tinysun212/swift-windows,tjw/swift,gottesmm/swift,gmilos/swift,brentdax/swift,tinysun212/swift-windows,dduan/swift,ken0nek/swift,apple/swift,CodaFi/swift,gregomni/swift,dduan/swift,xedin/swift,SwiftAndroid/swift,jopamer/swift,parkera/swift,devincoughlin/swift,allevato/swift,codestergit/swift,russbishop/swift,shahmishal/swift,aschwaighofer/swift,hughbe/swift,arvedviehweger/swift,kstaring/swift,adrfer/swift,sdulal/swift,allevato/swift,codestergit/swift,CodaFi/swift,emilstahl/swift,codestergit/swift,deyton/swift,mightydeveloper/swift,frootloops/swift,shajrawi/swift,IngmarStein/swift,tjw/swift,manavgabhawala/swift,xedin/swift,shahmishal/swift,benlangmuir/swift,swiftix/swift,codestergit/swift,tinysun212/swift-windows,apple/swift,return/swift,jmgc/swift,sschiau/swift,tardieu/swift,deyton/swift,sschiau/swift,deyton/swift,atrick/swift,kperryua/swift,jckarter/swift,kstaring/swift,jopamer/swift,tjw/swift,ben-ng/swift,aschwaighofer/swift,harlanhaskins/swift,cbrentharris/swift,tardieu/swift,gottesmm/swift,xedin/swift,dduan/swift,emilstahl/swift,sdulal/swift,russbishop/swift,roambotics/swift,therealbnut/swift,OscarSwanros/swift,hughbe/swift,tjw/swift,SwiftAndroid/swift,OscarSwanros/swift,felix91gr/swift,gribozavr/swift,gottesmm/swift,alblue/swift,jmgc/swift,kusl/swift,airspeedswift/swift,djwbrown/swift,ken0nek/swift,practicalswift/swift,natecook1000/swift,apple/swift,arvedviehweger/swift,danielmartin/swift,johnno1962d/swift,practicalswift/swift,sdulal/swift,gmilos/swift,MukeshKumarS/Swift,bitjammer/swift,tardieu/swift,milseman/swift,Ivacker/swift,practicalswift/swift,therealbnut/swift,alblue/swift,austinzheng/swift,deyton/swift,manavgabhawala/swift,therealbnut/swift,modocache/swift,jtbandes/swift,natecook1000/swift,arvedviehweger/swift,airspeedswift/swift,lorentey/swift,karwa/swift,kstaring/swift,gmilos/swift,kentya6/swift,aschwaighofer/swift,tinysun212/swift-windows,ken0nek/swift,ken0nek/swift,dduan/swift,xwu/swift,adrfer/swift,atrick/swift,rudkx/swift,glessard/swift,ben-ng/swift,natecook1000/swift,kstaring/swift,Ivacker/swift,jmgc/swift,milseman/swift,gribozavr/swift,hooman/swift,hughbe/swift,gmilos/swift,CodaFi/swift,kperryua/swift,djwbrown/swift,nathawes/swift,OscarSwanros/swift,dduan/swift,JGiola/swift,uasys/swift,rudkx/swift,xedin/swift,CodaFi/swift,tkremenek/swift,modocache/swift,xwu/swift,manavgabhawala/swift,ben-ng/swift,calebd/swift,JaSpa/swift,milseman/swift,russbishop/swift